How many civilian-owned firearms are there in the United States?

How to get close to this number

Anchor on the population and exceed it. The explanation gives the headline finding: more firearms than people. Ownership is concentrated — a minority of households own guns, but those that do often own several — so the total can exceed the population while most people own none. Concentration is what makes that arithmetic work.

The international share is the number that gives the figure meaning: around four percent of the world population holding something close to forty percent of the world's civilian firearms. A national total is hard to judge in isolation; expressing it as a share of a global total turns it into a comparison, and comparisons are what estimates need.

The caveat in the explanation is essential and unusually explicit: this is an estimate, not a count, because there is no national registry. The figure is modelled from manufacturing, import and survey data, so it carries real uncertainty and is dated. Any statistic about a thing that is deliberately not registered is a reconstruction, and it should always be labelled as one.